tty: split the lock up a bit further
The tty count sanity check may need the BKL, that isn't clear. However it
is clear that the count use of the lock is internal and independant of the
bigger use of the lock.
Furthermore the file list locking is also separately locked already
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index a19fef2..684f0e0 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -516,6 +516,8 @@
/* inuse_filps is protected by the single kernel lock */
lock_kernel();
check_tty_count(tty, "do_tty_hangup");
+ unlock_kernel();
+
file_list_lock();
/* This breaks for file handles being sent over AF_UNIX sockets ? */
list_for_each_entry(filp, &tty->tty_files, f_u.fu_list) {
@@ -529,6 +531,7 @@
}
file_list_unlock();
+ lock_kernel();
tty_ldisc_hangup(tty);
read_lock(&tasklist_lock);